Modem printing devices such as printers, copiers, and fax machines use certain materials that are consumed in the operation of the device. Examples of such materials are toner and ink. The device manufacturer will normally provide such materials in a disposable printing cartridge that is discarded when these materials are consumed. Often such cartridges also contain one or more components, such as a thermal inkjet print head, that have a limited lifespan in the operation of the printing device.
However, while the lifespan of the hardware components of the cartridge is limited, this lifespan will normally exceed the supply of consumable material available in the cartridge. Additional margin is also sometimes provided due to the various printing modes used by customers. For example, a customer who typically prints a succession of single page jobs will wear out a laser printer's photoconductor drum (OPC) much faster than a customer who normally prints larger jobs of 20 pages or more.
Thus, a cartridge designed to meet the needs of both types of customers may be capable of effective use even after the original supply of consumable substance is exhausted.
In many markets for printing devices, the printing cost per page is an important factor in the purchase decision of the disposable cartridge. Because of the desire to reduce the average printing cost per page, toner or ink cartridges are sometimes refilled by consumers with after-market tools and materials. Often the materials available in the after-market products are not manufactured to the same standards as the original materials used in the cartridge. Additionally, some consumers continue to refill and use cartridges beyond their intended useful life.
Refilling disposable cartridges can result in many printing problems including loss of definition, increased leakage, and printer damage or cartridge failure. These quality issues will often impact the reputation of the printing product.
To deal with the problems associated with refilling disposable cartridges, some attempts have been made to prevent the use of printing cartridges when the original supply of consumable substance is exhausted. However, as discussed above, often there is useful life remaining for the cartridge hardware when the consumable substance is exhausted, which cannot be effectively utilized by present methods
Throughout the drawings, identical reference numbers indicated similar, but not necessarily, identical, elements. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.